This invention relates to packaging for integrated circuits and more particularly to lead package for integrated circuits.
Typically the final process in the manufacture of an integrated circuit, packaging of an integrated circuit is attendant with several challenges that may prevent obtaining the intended operational characteristics of the integrated circuit. Packaging of an integrated circuit involves mechanically mounting the integrated circuit to the package and providing electrical connections between the integrated circuit and conductors of the package, typically called leads, to facilitate signal transmission between the integrated circuit and circuits outside of the package.
Referring to FIGS. 1 and 2, a typical lead package 10 includes a die pad 12, an integrated circuit 14 fixedly attached to die pad 12 with an adhesive compound 16 such as epoxy or solder. Package 10 includes a plurality of conductive leads 18 in electrical communication with integrated circuit 14 with one or more conductive wires 20. Die pad 12, integrated circuit 14, conductive wires 20, and a portion of conductive leads 18 are encapsulated with a suitable material, such as resin 22, with the remaining portion of leads 18 being exposed. In this manner, resin 22 hermetically seals die pad 12, integrated circuit 14, conductive wires 20, and a portion of conductive leads 18.
Drawbacks with this configuration are manifold. Firstly cross-talk between adjacent signal paths is difficult to control due to the inability to control the length of the wire 20, the pitch of leads and the integrated circuit input/output (I/O) impedance. Secondly, hermetically sealing the die pad 12 and integrated circuit 14 makes heat dissipation problematic.
A need exists, therefore, to provide an improved lead package for integrated circuits that overcomes the drawbacks of the prior art.